Black trisazo dyes.



p N 0 Drawing.

UNITED STATES PATENT OFFICE.

AUGUST BLANK AND CARL HEIDENREICH, 0F LEVERKUSEN, GERMANY, ASSIGNORS TO FARBENFABRIKEN VORM. FRIEDR. BAYER & 00., OF ELBERFELD, GERMANY, A

CORPORATION OF GERMANY.

BLACK TRISAZO DYES.

Our invention relates to the manufacture and production of new black cotton dyestuffs which are obtained by diazotizing the intermediate products obtained from 1 molecule of a tetrazotized para-diamino-diphenylamin compound and 1 molecule of an aminonaphthol sulfonic acid such as 2.5.7-01' 2.8.6-aminonaphthol sulfonic acid and combining the tetrazo compound thus obtained with 2 molecules of a meta-aminophenylglycin or with 1 molecule of such a glycin and 1 molecule of another azo dyestuff component. These new black dyestuffs are after being dried and pulverized in the shape of their alkaline salts black powders soluble in hot water with a black coloration. They yield upon treatment with stannous chlorid and hydrochloric acid a para-diamino-diphenylamin compound, a diaminonaphthol sulfonic acid and a glycin of a triaminobenzene. They are especially valuable for NH.CH1COOH It dyes cotton in full black shades which are fast to washing after treatment with formaldehyde. The new dye is after being dried and pulverized in the shape of its sodium salt a black powder which is soluble in hot water with a black coloration and which is soluble in concentrated sulfuric acid with a blue-black coloration. It yields upon treatment with stannous chlorid and hydrochloric acid para-diamino-diphenylamin, 2.7-diamino- 8 -naphthol- 6 sulfonic acid and the glycin of '1.2.4-triaminobenzene. One molecule of meta-aminophenylglycin may be replaced by resorcin, etc.

Example 2: 21.3 parts ofpara-diamino- Specification of Letters Patent.

Application filed May 28, 1912.

Patented Mar. 18,1913.

Serial No. 700,169.

the dyeing of cotton goods and are distinguished by their great fastness to light. The shades obtained from these dyes are rendered very fast to washing by an aftertreatment on the fiber with formaldehyde.

In order to illustrate the new process more fully the following examples are given, the parts being by weight Example 1 19.9 parts of para-diaminodiphenylamin are diazotized in the usual way with 18.8 parts of sodium nitrite and 65 parts of hydrochloric acid. The tetrazo solution is quickly added to a solutioncooled to 0 C.of 23.9 parts of 2.8.6-aminonaphthol-sulfonic acid in 500 parts of water and 42 parts of soda. The mixture is then acidulated with 105 parts of hydrochloric acid and diazotized with a solution 6.9 parts of sodium nitrite which requires about 2-l hours stirring at a temperature of 0 0. subsequently a solution of 33.2 parts of metaamino-phenylglycin in 500 parts of water and 42- parts of soda is cooled to about 05 C. and the above mentioned tetrazo coinpound is run into it. After several hours the mixture is heated to 50 C. and the dyestuif is salted out.

The dyestuffs correspond to the formula:

phenyltolylamin are tetrazotized as before described and combined with a solution of 23.9 parts of 2.5.7-aminonaphtho-l sulfonic acid in 500 parts of water and 42 parts of soda. The intermediate product is further diazotized with 6.9 parts of sodium nitrite and 105 parts of hydrochloric acid. A neutral solution of 16.6 parts of meta-aminophenylglycin is added to the diazo com pound and then sodium acetate until the meta-aminophenylglycin has disappeared. Subsequently a solution of 11 parts of resorcin is added and the solution is rendered alkaline with soda. After several hours the dyestuff is salted out. It dyes cotton in a bluish-black shade, which when aftertreated with formaldehyde changes to a full black fast to washing and to light.

We claim Similar dyestuffs can be obtained by replacing in these examples the meta-aminophenylglycin by meta-aminotolylglycin etc.

1. As new products the new black cotton trisazo dyestuffs which are after being dried and pulverized in the shape of their alkaline salts black powders soluble in hot water with a black coloration; yielding upon treat ment with stannous chlorid and hydrochloric acid a para-diamino-diphenylamin C0111- pound a diaminonaphthol sulfonic acid and a glycin of a triaminobenzene; dyeing cotton in full black shades which are fast to washing after treatment with formaldehyde, substantially as described.

2. *As a new product the herein described new black cotton trisazo dyestuff, which is after being dried and pulverized in the shape of its sodium salt a black powder soluble in hot water with a black coloration and soluble in concentrated sulfuric acid with a blueblack coloration; yielding upon treatment with stannous chlorid and hydrochloric acid para-diaminodiphenylamin, 2.7-diamino-8- naphthol-(i-sulfonic acid and the glycin of 1.QA-triaminobenzene; dyeing cotton in full black shades which are fast to washing and to light after treatment with formaldehyde, substantially as described.

In testimony whereof we have hereunto set our hands in the presence of two subscribing witnesses.

AUGUST BLANK. [n.sl CARL HEIDENREICH.

Vitnesses HELEN Norm, ALBERT NUFER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

